Скачать или смотреть Protecting Keystone Predators: Trophic Cascade and Ecosystem Destruction

Breaking News: The U.S. Fish and Wildlife Service has declared that the Gray Wolf Recovery Plan will not be released. This news comes alongside ongoing debates in congress discussing Section 128 in the proposed H.R.4754 bill, which aims to delist gray wolf protections from the Endangered Species Act across 44 states. Many conservation organizations are fighting back, with Humane World calling the US government’s handling of wolf conservation an “insult to animals and prevailing science”.

But why the focus on wolves specifically? Why is the potential loss of wolves so worrying, and why should the average person care? To explain this, we’d like to tell the story of one of the most iconic examples of the loss and reintroduction of a keystone species into the environment.

Yellowstone National Park is one of the most biodiverse places in North America. Biodiversity can be defined as the variety of life and relationships interacting in an ecosystem. The presence of many species is crucial for the health and productivity of an ecosystem.

However, the balance of this park relies on the presence of one species: the wolf.

In 1926, wolves were eradicated from Yellowstone National Park. The result of a years-long eradication effort. However, the loss of the keystone predator would cause devastating effects on the environment. This is known as a trophic cascade- an ecological process in which the removal of the top predator causes both direct and indirect effects all throughout the food web. In this case, this top predator is a keystone species: a species who plays such a large role in their habitat, that the removal of this species can cause complete destruction of the ecosystem.

Following the eradication of wolves, the ungulate population boomed. Not only did this increase the amount of forage they were eating- but it changed their behavior patterns as well. With no predators to run from, elk herds became nearly stationary- often destroying the foraging plant population in a single area before moving on. The decline in woody plants contributed to the reduction of birds and beavers in the park, another keystone species whose presence is essential for maintaining wetland habitats. The loss of beavers and their dams changed the streams, causing increases in erosion and disrupting habitats. The park’s downward spiral in health was attempted to be resolved by culling the elk population, but by then, it was too late.

Famously, the restoration of the wolf population in 1995 is what finally restored health to the park. In the years following, the ungulate population decreased, allowing the plant population to recover, which gradually restored the health and biodiversity of the ecosystem as a whole.

Knowing this, we must realize that wolves must be protected. Advocacy groups urge people to email their representatives to emphasize the importance of wolves on the ecosystem. Education worldwide is crucial to ensure that these anti-scientific laws are not repeated globally, which could cause similar trophic cascades in any ecosystem where wolves are keystone species. Now more than ever, it is important for all of us to be educated and passionate, so we may urge our governments to protect keystone species, protect biodiversity, and protect the global ecosystem.